AFTER last season's disappointment, Leinster at least guaranteed qualification for the quarter-finals this term but, to advance any further, it seems inevitable they will have to do it the hard way.

Nothing, whether it is contract sagas or qualification routes, seems to come easy to them these days but they remain confident that they will come good, even though a five-try triumph here papered over a whole host of cracks. Ian Evans' first-half dismissal for dancing all over the head of Mike McCarthy -- Ospreys complained little afterwards -- ruined the contest, even if both sides had been doing a good job of that themselves until that point.

"It turned into a bit of a circus after that and we butchered three tries," admitted Leinster coach Matt O'Connor. "The scheduling didn't help at all. We have to be better than that. We've work to do."

WHEEZING

It was 3-3 with 15 men but 17-3 at the break; after that it was merely a matter of how many tries a wheezing Leinster could score. Even the five they managed will probably not be enough to avoid an April road trip.

"We had to stick to our guns because it was a slow game," said man of the match Cian Healy, who scored one of the tries in a performance where a penalty try double illustrated a farcical enough occasion at times.

"It came off nicely in the end for us. We're plugging away. It's happened us in previous seasons when we're winning and not playing our best rugby. We're hoping it comes good for us at the right time of the season.

"We believe in what we can do. It would be great to have a game in Dublin but we can go anywhere and win anywhere."

Leinster's anxiety to get the early upper hand betrayed them with knock-ons from Jimmy Gopperth and Sean Cronin in the contact area as the Ospreys proved they were up for the scrap with some stern defence.

The Ospreys were anxious themselves and, after their own knock-on deep in their own territory, Adam Jones disappeared beneath the RDS turf and Jimmy Gopperth nailed a settling three-pointer after just eight minutes.

Leinster were keen to develop a quick off-loading game, too keen when Rhys Ruddock was isolated near halfway after his side ceded the gainline with a loose pass from Gopperth.

Dan Biggar, who has managed a streak of 35 from 35 kicks already this term, was 20 from 20 in this competition and, despite being between the 10-metre line and halfway, he made it 21 in a row with the aid of the crossbar in the 13th minute.

There is always needle between these sides and the home crowd were already on referee Romain Poite's back before the Ospreys appeared to be stamping all over McCarthy.

McCarthy had to depart; Evans, identified via endless television replays, followed and, with just a quarter of the game gone, the entire momentum of the contest had switched decisively.

Maintaining their interest with 15 men was a dubious enough assignment for the Ospreys; they have rarely demonstrated the type of aptitude that suggests they could so with merely 14. Matthew Morgan shifted to out-half while Biggar went to second receiver and Ryan Jones soon became their second injury casualty.

Leinster looked more spooked by the numerical advantage, messing up a couple of now dominant scrums as they sought penalty advantages. To be frank, it was all a bit messy.

When they did win a penalty, Leinster splintered a driving maul and allowed the Ospreys a relieving touchfinder. The triple champions were not convincing title pretenders; like the proverbial GAA match, the 15 men were struggling against 14.

Brian O'Driscoll, of all people, threw a Hail Mary skip-pass in his own half; bizarrely, there was no leadership and you sensed they were the side craving the half-time cuppa.

Only belatedly did they made their greater presence felt.

After one of Gopperth's better kicks, Leinster won the decision on the floor and kicked to touch; from the ensuing line-out drive, Poite, never afraid to seize the moment, whistled for a 35th-minute penalty try after numerous infringements from the men in white.

Suitably liberated, Martin Moore typified their relief with a lung-busting burst from midfield. He off-loaded to Gopperth but unfortunately the Australian dotted the ball down on Rhys Webb's leg.

No matter. Back came Leinster and, punishing Ospreys with a series of fierce carries, the indomitable Healy capped off a fine half with the final scoring touch, converted by Gopperth for a 17-3 lead that had seemed improbable just a few minutes earlier.

As if the game couldn't reach any further depths of farce, replacement Ospreys hooker Scott Baldwin was forced off and, bizarrely, a substitute remained footloose on the sidelines.

Prop Adam Jones threw into the line-out, much to merriment of the home crowd, and his side turned over, much to their further amusement.

Smiles turned to groans, though, as Leinster butchered their second try of the night, Shane Jennings managing to work his way into an offside position as Zane Kirchner attempted to offload a scoring pass inches from the line to Dave Kearney.

Then, as Gopperth became the second player to leave the fray with claret gushing from his bonce like the first harvest of the Bordeaux spring, Jordi Murphy arrived temporarily to slot in at inside-centre, reliving a former life.

COMEDY

It was a comedy of errors but Leinster, lacking control and authority, weren't smiling as the clock ticked funereally towards the 80th minute; this was rugby written by the creators of Father Ted.

In keeping with the theme of the game, Leinster scored their second penalty try of the night just after the hour mark when, with Ospreys apparently contesting the scrum once more, they concertinaed.

With their bench and scrum now dominant factors, Eoin Reddan knocked on beyond the posts. The biggest cheer of the night was reserved for the remarkable return of Richardt Strauss, miraculously back on the field so swiftly after October's heart surgery.

Minutes later, the hard-running Murphy, playing his orthodox position in the back-row now, took a great line to secure the bonus, and Boss followed him over.

Not without its complications then. But it's been that kind of week for Leinster.